This article explores the influence of social origin on overeducation across various fields of study. With the expansion of higher education most advantaged classes seek qualitative and quantitative advantages to differentiate themselves from other graduates. Although credentials are direct signals of productivity they can also be viewed by employers as indirect signals of non-cognitive skills, which can be acquired through family socialization. These credentials may explain differences in overeducation among graduates of different fields of study and social origin. Parental educational background and occupation are relevant characteristics from which individuals gain useful skills and information to avoid overeducation in the labour market. Using data from the Italian Graduates Employment Survey (ISTAT in Indagine Statistica sull'Inserimento Professionale dei Laureati. Istituto nazionale di statistica, Rome, 2007) this article provides evidence that graduates from fields of study that do not lead to a specific occupation (e.g. Humanities, Political and Social Sciences) decrease their risk of overeducation when their fathers belong to the professional class, but it has no influence on graduates from occupationally focused fields of study (e.g. Engineering and Medicine). These results are consistent even after controlling for the possible use of social networks when looking for a job.